GTEM-AEZ (Global Trade and Environmental Model—Agro-Ecological Zones)

GTEM-AEZ (Global Trade and Environmental Model—Agro-Ecological Zones) is a dynamic recursive Computable General Equilibrium (CGE) model derived from the GTEM-C model. It is part of the GTEM suite, which includes GTEM-Food and GTEM-Resources, developed by CSIRO. The model accounts for multiple land use and land cover types by dividing land endowment into 18 Agro-Ecological Zones (AEZs). This is achieved by using a Constant Elasticity of Substitution function to represent the substitution of 18 AEZs land types in the production function of a land-use sector, and each AEZ land is supplied by a Constant Elasticity of Transformation function to account for the heterogeneity in land rents and physical land area constraints among land-use sectors.

To develop GTEM-AEZ we used AEZ land data from the Global Trade Analysis Project (GTAP) Land Use and Land Cover (LULC) database, which contains information on 18 AEZs and seven land covers. The model’s main objective is to facilitate the exploration of various issues such as the impact of land use change and associated emissions, climate change, food security, technological development, emissions mitigation options, Sustainable Development Goals, net zero emissions transition, and more.